package adapter

import (
	"bytes"
	"encoding/base64"
	"reflect"
	"text/template"
	"time"

	"github.com/Masterminds/sprig/v3"
)

type Proxy struct {
	Sort   int
	Name   string
	Server string
	Port   uint16
	Type   string
	Tags   []string

	// Security Options
	Security          string
	SNI               string // Server Name Indication for TLS
	AllowInsecure     bool   // Allow insecure connections (skip certificate verification)
	Fingerprint       string // Client fingerprint for TLS connections
	RealityServerAddr string // Reality server address
	RealityServerPort int    // Reality server port
	RealityPrivateKey string // Reality private key for authentication
	RealityPublicKey  string // Reality public key for authentication
	RealityShortId    string // Reality short ID for authentication
	// Transport Options
	Transport   string // Transport protocol (e.g., ws, http, grpc)
	Host        string // For WebSocket/HTTP/HTTPS
	Path        string // For HTTP/HTTPS
	ServiceName string // For gRPC
	// Shadowsocks Options
	Method    string
	ServerKey string // For Shadowsocks 2022

	// Vmess/Vless/Trojan Options
	Flow string // Flow for Vmess/Vless/Trojan
	// Hysteria2 Options
	HopPorts     string // Comma-separated list of hop ports
	HopInterval  int    // Interval for hop ports in seconds
	ObfsPassword string // Obfuscation password for Hysteria2
	UpMbps       int    // Upload speed in Mbps
	DownMbps     int    // Download speed in Mbps

	// Tuic Options
	DisableSNI           bool   // Disable SNI
	ReduceRtt            bool   // Reduce RTT
	UDPRelayMode         string // UDP relay mode (e.g., "full", "partial")
	CongestionController string // Congestion controller (e.g., "cubic", "bbr")

	// AnyTLS
	PaddingScheme string

	// Mieru
	Multiplex string

	// Obfs
	//Obfs     string // obfs, 'none', 'http', 'tls'
	//ObfsHost string // obfs host
	//ObfsPath string // obfs path

	// Vless
	XhttpMode  string // xhttp mode
	XhttpExtra string // xhttp path

	// encryption
	Encryption              string // encryption，'none', 'mlkem768x25519plus'
	EncryptionMode          string // encryption mode，'native', 'xorpub', 'random'
	EncryptionRtt           string // encryption rtt，'0rtt', '1rtt'
	EncryptionTicket        string // encryption ticket
	EncryptionServerPadding string // encryption server padding
	EncryptionPrivateKey    string // encryption private key
	EncryptionClientPadding string // encryption client padding
	EncryptionPassword      string // encryption password

	Ratio           float64 // Traffic ratio, default is 1
	CertMode        string  // Certificate mode, `none`｜`http`｜`dns`｜`self`
	CertDNSProvider string  // DNS provider for certificate
	CertDNSEnv      string  // Environment for DNS provider

	// Simnet Options (server-side config; per-user psk/key_id are derived at
	// render time from UserInfo, never stored on the Proxy).
	SimnetPsk                          string // server-side PSK (key_id=0), used for AF derivation
	SimnetKeyID                        int    // server key id (0)
	SimnetTicketID                     string
	SimnetPath                         string
	SimnetCarrier                      string
	SimnetAfEnabled                    bool
	SimnetAfPathMode                   string
	SimnetAfPathPrefix                 string
	SimnetAfPathSuffix                 string
	SimnetAfMagicMode                  string
	SimnetAfResponseJitterMs           int
	SimnetAfHandshakePolymorphism      bool
	SimnetAfSettingsJitter             bool
	SimnetAfFakeHeaderInjection        bool
	SimnetFallbackEnabled              bool
	SimnetFallbackTargetScheme         string
	SimnetFallbackTargetHost           string
	SimnetFallbackTargetPort           int
	SimnetFallbackHostHeader           string
	SimnetFallbackTLSSNI               string
	SimnetClientMaxConcurrentStreams   int
	SimnetClientMaxStreamsPerSession   int
	SimnetClientSessionIdleTimeoutSecs int
	SimnetClientMaxUDPSessions         int
}

type User struct {
	Password     string
	SubscribeID  int64 // user_subscribe.id — derives the simnet per-user key_id
	ExpiredAt    time.Time
	Download     int64
	Upload       int64
	Traffic      int64
	SubscribeURL string
}

type Client struct {
	SiteName       string            // Name of the site
	SubscribeName  string            // Name of the subscription
	ClientTemplate string            // Template for the entire client configuration
	OutputFormat   string            // json, yaml, etc.
	Proxies        []Proxy           // List of proxy configurations
	UserInfo       User              // User information
	Params         map[string]string // Additional parameters
}

func (c *Client) Build() ([]byte, error) {
	var buf bytes.Buffer
	funcMap := sprig.TxtFuncMap()
	funcMap["buildOmnxtSimnetConfigs"] = buildOmnxtSimnetConfigs
	funcMap["buildOmnxtProtocolLinks"] = buildOmnxtProtocolLinks
	tmpl, err := template.New("client").Funcs(funcMap).Parse(c.ClientTemplate)
	if err != nil {
		return nil, err
	}

	proxies := make([]map[string]interface{}, len(c.Proxies))
	for i, p := range c.Proxies {
		proxies[i] = StructToMap(p)
	}

	err = tmpl.Execute(&buf, map[string]interface{}{
		"SiteName":      c.SiteName,
		"SubscribeName": c.SubscribeName,
		"OutputFormat":  c.OutputFormat,
		"Proxies":       proxies,
		"UserInfo":      c.UserInfo,
		"Params":        c.Params,
	})
	if err != nil {
		return nil, err
	}

	result := buf.String()
	if c.OutputFormat == "base64" {
		encoded := base64.StdEncoding.EncodeToString([]byte(result))
		return []byte(encoded), nil
	}

	return buf.Bytes(), nil
}

func StructToMap(obj interface{}) map[string]interface{} {
	m := make(map[string]interface{})
	v := reflect.ValueOf(obj)
	t := reflect.TypeOf(obj)

	for i := 0; i < v.NumField(); i++ {
		field := t.Field(i)
		m[field.Name] = v.Field(i).Interface()
	}
	return m
}